THE BEHAVIOUR OF SPENT FUEL UNDER TRANSIENT ACCIDENT CONDITIONS (PREPRINT IBRAE-1997-12)

Preprint IBRAE-97-12

Likhanskii V.V., Matveev L.V. 

The survey of experimental investigations of nuclear fuel behaviour during its quick heatup is carried out. The models are proposed which describe various modes of relaxation of grain boundary porosity at sharp temperature increase in the absence of irradiation. The criterium of the beginning of the "brittle" mode of the grain boundary bubbles relaxation and the expression for their final radii are presented. The rate of diffusion growth of the grain boundary bubbles is calculated, and the conditions are pointed out for which the diffusion relaxation of the bubbles takes place. In addition various stress sourses in inhomogeneously heated fuel pellet are considered. 

Bibliographical reference

Likhanskii V.V., Matveev L.V. THE BEHAVIOUR OF SPENT FUEL UNDER TRANSIENT ACCIDENT CONDITIONS. Preprint IBRAE-97-12. Moscow. Nuclear Safety Institute. July 1997. 22 p. — Refs.: 29 items.